INVESTIGADORES
APESTEGUIA Sebastian
congresos y reuniones científicas
Título:
New Carcharodontosauridae (Dinosauria, Theropoda) from the early Late Cretaceous of Neuquén, Argentina, yields light on the anatomy of the group.
Autor/es:
CANALE, JUAN I.; APESTEGUÍA, SEBASTIÁN; MAKOVICKY, PETER J.; GALLINA, PABLO A.; NATHAN SMITH; MITCHELL, JOHN; GIANECHINI, FEDERICO A.; ALEJANDRO HALUZA
Lugar:
san luis
Reunión:
Encuentro; Reunión de comunicaciones de la Asociación Paleontológica Argentina; 2017
Institución organizadora:
universidad de san luis
Resumen:
Although nearly a dozen species of Carcharodontosauridae are recognized, many anatomical aspects of derived members within Giganotosaurini remain poorly known. A recently recovered specimen with carcharodontosaurid affinities (MMCh-PV 65) from the Huincul Formation (Cenomanian), provides new information on the cranial and appendicular anatomy of the group. The new specimen exhibits unique traits, including a jugal with a "step" in the posterior margin of the postorbital process, a postorbital with a lateral bump on the squamosal process, and proximal caudal vertebrae with extensive pneumatic openings in the bases of the neural spines above the postzygapophy ses. Important features distinguish MMCh-PV 65 from the other two carcharodontosaurids described from the same formation (Mapusaurus roseae Coria and Currie 2006, and Taurovenator violantei Motta et al. 2016), and provide evidence for a possible new taxon. A preliminary phylogenetic analysis recovers the specimen nested within Giganotosaurini alongside other South American carcharodontosaurids, by having a postorbital process of the jugal with a wide base, absence of pneumatic openings on the caudal vertebral centra, and a pubic shaft that is straight in lateral view. The new material has longer hindlimbs, and proportionally smaller and more gracile skull bones compared to Giganotosaurus carolinii Coria and Salgado 1995. In the broader context of Allosauroidea evolution, this new specimen demonstrates that derived carcharodontosaurids show heterochronic patterns in the development of larger sizes, and proportionally shorter arms and larger skulls than basal allosauroids such as Allosaurus.